The Product: Convertible Car Seat (5-65 LBS)

A convertible car seat is commonly used from the time your baby outgrows an infant carrier until it’s time for a booster seat. A convertible seat should be used in the rear-facing position until your baby is at least 1 year old and weighs 20 pounds, at which point you can switch the seat to the forward-facing position. A convertible seat that accommodates up to 65 pounds will make the transition to a booster seat easier and will keep your child in a five-point harness longer. In all cases, it is important to read the manual for your specific car seat and even your car, because guidelines are always changing.

Recommendation: Britax Diplomat Car Seat Review

The Britax Boulevard is now my top recommended Britax car seat. A big thanks goes out to BabyCenter Store and Britax USA for providing us with a demo. The Britax Boulevard is the same size as its better known cousin the Marathon, but it comes with high-end side-impact features as well as extra padding and an easy-to-use height adjustment feature. When I wrote about the Marathon, I recommended going with the larger seats that have the higher weight limit (65 lbs) and I stick by that choice over the Roundabout / Diplomat seats if you have room in your car.

The Boulevard’s True Side Impact Protection (TSIP) includes deep side walls and head support to better protect your child in the case of a side collision. The system is also a huge improvement over the original side impact system that was developed by Britax for the quickly discontinued Britax Wizard, which was too obtrusive. The protection was so close to my child’s head that it made me feel claustrophobic. The newer TSIP system has redesigned side wings that stay out of the way—yet provide great neck support during naps. My son hasn’t noticed the difference from his old Marathon car seat.

The other really nice feature of the Boulevard (inherited from the old Britax Advantage seat) is the multi-position head rest.The height of the head rest can be adjusted to fit any size without removing the seat and unhooking the straps. The Boulevard also has a removable body pillow to keep newborns snug in the rear-facing position, as well as the Britax LATCH Bar, which is a freestanding bar on the outside of the seat that makes it simple to attach the seat using the LATCH anchors.

Here is a quick recap of the features the Britax Boulevard has over the better known Marathon:

• True Side Impact Protection™
• Body pillow
• Multi-position head rest and harness heights 

Devil's Advocate: